new to MFP, some questions for those who have benefited from

sister83

hi!
i'm 23 this year, 5' 6" and 130lbs. trying to get to my previous weight which was 121 a few years back which is a mystery how i even gained the weight considering i ate like a glutton during my school days .
But anyways i've been Bodyrocking for about 2 months or so (did a week of turbofire before that) and i just started MFP and Insanity yesterday.
Its kinda confusing because according to MFP, i should be consuming 1500 calories a day in order to reach my goal in 5 weeks or so.
However, according to the formula found in insanity i should be consuming 1700+ a day. so my qn is which is safer to follow as a guide?